Getting a Betta! What should I know?

Hi guys, I'm getting a betta fish this afternoon and I'm super excited. I plan on getting him/her a 2.5 gallon tank, with an air filter. I'll fill it with colorful pebbles (not sure if that makes a difference) and a couple pieces of plastic foliage for places for him/her to hide. I'll change a quarter of the water once a week (that's what I read), and will feed him once daily with some flakes. Is there anything I should be careful about? Be sure to know? Thanks! I'm looking forward to my own little fish friend :)